Vivus, Racing Rivals, Says Diet Drug Did Well in Trials

By ANDREW POLLACK

Published: September 10, 2009

Vivus, a drug developer, said Wednesday that its weight-loss drug produced strong results in two late-stage clinical trials, sending the company's share price soaring.

Vivus said it would apply by the end of the year for Food and Drug Administration approval of the drug, which is called Qnexa, and would start looking for a pharmaceutical company to help market the product.

''This is better than we've seen before,'' Dr. Louis J. Aronne, director of the comprehensive weight control program at New York-Presbyterian/Weill Cornell medical center, said of the results. Dr. Aronne was not involved in the trials but has been an adviser to Vivus and many other companies developing drugs to treat obesity.

Shares were up 70.77 percent, to $11.80, and continued to rise after hours.

With one-third of American adults said to be obese, a successful drug could potentially have billions of dollars in sales. Existing drugs have been plagued by side effects and some have been withdrawn from the market.

Vivus, which is based in Mountain View, Calif., is in a race with two other companies, Arena Pharmaceuticals and Orexigen Therapeutics, both of San Diego, to bring a new diet drug to market.

While the three drugs have not been compared head to head in clinical trials, some analysts said the results achieved by Qnexa were better than those reached by the Orexigen and Arena drugs in their respective studies.

Vivus announced results from two randomized trials, one involving 1,267 morbidly obese patients and the other involving 2,487 overweight and obese patients with other problems like high blood pressure or diabetes. The results have not been peer-reviewed.

After a year, patients on the highest dose of Qnexa had lost an average of 10.4 percent of their weight in one trial and 11 percent in the other, compared with 1.6 percent to 1.8 percent for those taking a placebo. That translates to weight loss of about 9 percent after subtracting the placebo effect, exceeding the F.D.A's requirement of 5 percent.

Although nearly 40 percent of the patients taking the high dose of Qnexa did not complete a year of treatment, those who did lost an average of 30 pounds in one trial and 37 pounds in the other.

About 70 percent of patients taking the high dose of Qnexa in both trials lost at least 5 percent of their body weight, compared with 20 percent or so of those taking a placebo. That meets another F.D.A. hurdle that at least twice as many patients on a drug as on a placebo lose 5 percent of their body weight.

Qnexa, taken once a day, is a combination of low doses of two drugs. One is phentermine, a diet drug that was part of the so-called fen-phen combination. (The other drugs in that combination were removed from the market for causing heart valve problems.)

The other drug in Qnexa is topiramate, an epilepsy drug sold as Topamax by Johnson & Johnson that is now open to generic competition.

Vivus said the main side effects of Qnexa were dry mouth, a tingling in the fingers and toes, and constipation. It said it found no evidence of depression, suicidal behavior or cognitive problems, possible side effects which are concerns the F.D.A. has about drugs that act on the central nervous system.